Milestone for Salesforce Tower: Now the tallest in the West

The view of San Francisco from the 60th floor of the tower during a topping off ceremony as the final steel beam was moved into position on the Salesforce Tower in downtown San Francisco, Ca. on Thurs. April 6 2017. less

The view of San Francisco from the 60th floor of the tower during a topping off ceremony as the final steel beam was moved into position on the Salesforce Tower in downtown San Francisco, Ca. on Thurs. April 6 ... more

The view of San Francisco from the 60th floor of the tower during a topping off ceremony as the final steel beam was moved into position on the Salesforce Tower in downtown San Francisco, Ca. on Thurs. April 6 2017. less

The view of San Francisco from the 60th floor of the tower during a topping off ceremony as the final steel beam was moved into position on the Salesforce Tower in downtown San Francisco, Ca. on Thurs. April 6 ... more

With its final steel beam hoisted into place, San Francisco's Salesforce Tower today became the tallest occupiable building west of the Mississippi River.

Technically, new Wilshire Grand building in Los Angeles will be 30 feet taller than Salesforce, but that's because of a longer spire topping the high-rise. In terms of human occupancy, the 1,070-foot Salesforce Tower will have the highest floor.

Salesforce CEO Marc Benioff celebrated the completion of the structural phase of the tower, which has been under construction for four years. That includes all the steel and concrete work. Some 92,000 cubic yards of concrete were poured for the project.

Last week workers laid concrete for the top floor of the Salesforce Tower. Senior Construction Manager Chris Vaughn-Hulbert talks about the construction of the tower, which will be the tallest building in San Francisco.

Media: MediaOS Video

The glass facade of the 61-story building at Mission and 1st streets is steadily coming up, with workers building out the skeleton and installing windows.

The Salesforce Tower will have 1.4 million square feet of tenant space, and each floor plate averages about 25,000 square feet per floor.

Unlike the sinking Millennium Tower, only a block away, the Salesforce Tower is anchored to bedrock.

For 43 years, the Transamerica Pyramid was the tallest structure in San Francisco, but Salesforce obliterated that record. The tower dwarfs the iconic pyramid.

Salesforce will occupy floors three to 30 and the top two levels, 60 and 61, on the tower.